I picked up this project up again now that its warm. I decided to start with another bench test of the circuit. The linear voltage regulator was putting out a very nice consistent 4.99V which is exactly where it should be. Then, I tested the dc-dc converter output and it was sending out a solid 15.6V. Not exactly what it should be (a bit high), but that seems quite reasonable. No smoking gun, okay, lets move ahead. I did notice the 7805 linear voltage regulator was getting quite warm, so I added a heat sink to it.
This afternoon I decided to put the circuit back on the car. I noticed that the fuse connector I made fit in very nice, good connection. However, the ground connector which was just a bent piece of metal barely was making contact. So, I rebent the connector to get a better connection. This time it fit in nice and snug. Could that be all it was?
I got it all plugged in and started the car up. Sure enough, no charging!
While I was working on things, I also current tested the circuit. That little voltage regulator is not an efficient little device. It draws .08A or 80mA. This doesn't sound like much, but over 24 hours it adds up to 2 amp hours. The battery should be around 75 amp hours. This means the circuit will drain 2.6% of the total battery capacity every day. Not horrible, but not good either.
So, I'll be testing this for a few days to make sure it is stays working. For now, the Mirage is all tucked in for the night. I'm looking forward to tomorrows commute.
